Monterrey has a semi-arid subtropical climate (Köppen BSh), with hot summers that regularly push past 35°C (95°F) and mild winters where daytime highs hover around 20°C (68°F). The city sits at 540 meters (1,770 feet) above sea level in a valley surrounded by the Sierra Madre Oriental, which traps heat and blocks Pacific moisture. Annual rainfall averages 590 mm (23 inches), mostly concentrated between May and October during the North American Monsoon. September is the wettest month at 150 mm (5.9 in), often from tropical cyclone remnants. Winters are dry. December averages just 15 mm (0.6 in) of rain. Humidity stays moderate year-round at 60 to 67 percent, though summer afternoons feel muggy when temperatures combine with residual moisture.
Monterrey Weather by Month: January
January is Monterrey’s coolest month. Average highs reach 20°C (68°F) and lows drop to 8°C (46°F). Cold fronts from the north can push overnight temperatures close to freezing, though frost is rare in the city center. Rainfall is minimal at 17 mm (0.7 in) across 2 to 3 days. You will need a jacket for mornings and evenings, but afternoons are pleasant for walking the Macroplaza. Sunshine averages 6 hours per day.
Monterrey Weather by Month: February
February warms slightly with highs of 22°C (72°F) and lows around 10°C (50°F). Rainfall stays low at 15 mm (0.6 in). This is one of the driest months of the year. Clear skies dominate and sunshine increases to 7 hours daily. Cold snaps still occur when Arctic air masses push south across the Texas border, 220 km (137 miles) north. Layers work well: a light sweater for daytime, a heavier jacket for evening.
Monterrey Weather by Month: March
March brings spring warmth with highs climbing to 26°C (79°F) and lows at 14°C (57°F). Rainfall remains scarce at 20 mm (0.8 in) over 3 days. This is a popular month for hiking Chipinque and La Huasteca before the summer heat arrives. Wind picks up in March, with gusts funneling through the mountain valleys. UV levels increase noticeably. Use sunscreen at elevation. Sunshine reaches 7.5 hours per day.
Monterrey Weather by Month: April
April marks the real start of hot weather. Highs average 30°C (86°F) and lows settle at 18°C (64°F). Rainfall jumps to 40 mm (1.6 in) as the monsoon pattern begins to form. Afternoon thunderstorms become possible, particularly in the second half of the month. The mountains surrounding the city trap heat, and temperatures above 35°C (95°F) are common by late April. Plan outdoor activities for mornings before 11:00 AM. Sunshine averages 8 hours per day.
Monterrey Weather by Month: May
May is hot and increasingly wet. Highs reach 33°C (91°F), lows 21°C (70°F), and rainfall jumps to 60 mm (2.4 in) across 6 days. Afternoon heat indices can exceed 38°C (100°F). The combination of heat and rising humidity makes midday uncomfortable for outdoor sightseeing. Thunderstorms develop rapidly in late afternoon, often with intense downpours lasting an hour. This is the start of the rainy season in northern Mexico. Air conditioning is essential in your hotel room.
Monterrey Weather by Month: June
June continues hot with highs of 34°C (93°F) and lows of 23°C (73°F). Rainfall averages 70 mm (2.8 in) over 7 days. This is the first month where rain becomes a regular feature rather than an occasional event. Mornings are typically clear, with clouds building by 2:00 PM and storms breaking between 4:00 and 6:00 PM. The Sierra Madre Oriental creates orographic lift that intensifies precipitation on the mountain slopes. Humidity reaches its annual peak at 67 percent.
Monterrey Weather by Month: July
July brings the highest rainfall of the summer at 80 mm (3.1 in) across 8 days. Highs stay at 34°C (93°F), lows 23°C (73°F). The monsoon trough sits over northern Mexico, drawing moisture from both the Gulf of Mexico and the Pacific. Rain falls as short, intense thunderstorms rather than all-day drizzle. Flooding can occur in low-lying areas of the city after heavy downpours. Despite the rain, mornings offer 5 to 6 hours of sunshine before clouds build.
Monterrey Weather by Month: August
August is the hottest month with average highs of 35°C (95°F) and lows of 23°C (73°F). Heat waves can push temperatures above 40°C (104°F) for several consecutive days. Rainfall decreases slightly to 70 mm (2.8 in) over 7 days. Thunderstorm activity remains regular. The combination of extreme heat and humidity creates the most uncomfortable conditions of the year. Museums like MARCO and Museo de Historia Mexicana provide air-conditioned refuge during peak afternoon hours.
Monterrey Weather by Month: September
September is Monterrey’s wettest month at 150 mm (5.9 in) across 9 days. Highs dip slightly to 31°C (88°F) and lows to 21°C (70°F). Tropical cyclones from both the Atlantic and Pacific can bring several days of heavy rain, as happened with Hurricane Alex in 2010 which dumped over 500 mm (20 in) on the city. Flood risk peaks this month. Despite the rain, temperatures remain warm. The Festival Internacional Santa Lucía begins in late September, and most events are indoors or under covered venues.
Monterrey Weather by Month: October
October brings relief. Highs drop to 27°C (81°F) and lows to 17°C (63°F). Rainfall moderates to 70 mm (2.8 in) over 6 days early in the month, then tapers off sharply by late October. This is one of the best months for visiting Monterrey: temperatures are comfortable, rain decreases, and the mountain landscapes turn green from summer moisture. Sunshine averages 6.5 hours. The cultural calendar is full with Santa Lucía festival events.
Monterrey Weather by Month: November
November is dry and mild. Highs average 23°C (73°F), lows 12°C (54°F), and rainfall drops to 25 mm (1.0 in) over 3 days. Skies clear and humidity falls to comfortable levels. This is peak season for outdoor activities like hiking Cerro de la Silla and exploring Grutas de García. The first cold fronts of winter arrive late in the month, sometimes dropping temperatures by 10°C (18°F) overnight. Pack a sweater for evenings at outdoor restaurants in Barrio Antiguo.
Monterrey Weather by Month: December
December is the driest month at 15 mm (0.6 in) of rain over 2 days. Highs reach 20°C (68°F), lows fall to 8°C (46°F). Cold fronts from the United States can bring several days of overcast skies and temperatures below 10°C (50°F). Snow is extremely rare in the city center but the surrounding peaks of the Sierra Madre Oriental sometimes get a dusting above 2,000 meters. The Luztopía Christmas light festival runs through December at Parque Fundidora, drawing large crowds on weekend evenings.
For a detailed breakdown of seasonal conditions and month-by-month recommendations, see our best time to visit Monterrey guide.
